Clinical differences of early and late-onset myasthenia gravis in 985 patients

Objective: The clinical differences of early-onset myasthenia gravis (EOMG) and late-onset MG (LOMG) have not been elucidated in China. In order to clarify this, a retrospective study was conducted in 985 MG patients, whose disease duration was longer than 3 years.

Methods: These patients were separated into EOMG and LOMG according to the onset age of 50 years. The clinical differences including demographics, clinical features, thymus abnormalities and comorbidities of EOMG and LOMG patients were analyzed.

Results: Results indicated that 485 were males and 500 were females, 714 were EOMG and 271 were LOMG. Female was more common in EOMG and male was more common in LOMG (p = 0.003). The peak onset age was 0–4 years in EOMG and 55–59 years in LOMG. Ocular MG (OMG) was more common in EOMG and generalized MG (GMG) was more common in LOMG (p = 0.004). The transformation rate of OMG to GMG was higher in LOMG (p = 0.002). The positive incidence of repetitive nerve stimulation (RNS) was higher in EOMG (p = 0.026). Thymoma was more frequent in LOMG (p = 0.017) and thymic hyperplasia was more frequent in EOMG (p < 0.001). Hyperthyroidism was more common in EOMG (p = 0.017) and diabetes was more common in LOMG (p < 0.001).

Conclusion: These results have potential significance for the recognition of clinical features and the determination of management strategies in EOMG and LOMG.     

High anti-EBNA-1 IgG levels are associated with early-onset myasthenia gravis

Background: Myasthenia gravis (MG) is an autoimmune disorder mediated by antibodies against the acethylcholine receptor (AchR) of the neuromuscular junction in the majority of patients. Methods: Here, we examined IgG antibodies against the type 1 nuclear antigen of Epstein‐Barr virus (EBNA‐1) in the sera of 158 patients with MG compared to 184 healthy controls. Results: Although serum concentration in the sera was not different, high anti‐EBNA‐1 IgG titers (above 90th percentile of the normal values) were more common in the patients (26.6 vs. 16.3%, P = 0.024). In addition, high EBNA‐1 IgG levels occurred more frequently amongst the 94 patients with early‐onset myasthenia gravis (EOMG, 30.8%) as compared to the 64 patients with late‐onset disease (LOMG, 14.1%) (P = 0.021). Using multiple logistic regression, high serum concentration of the anti‐EBNA‐1 IgG antibodies was significantly associated with EOMG (OR: 3.17, P = 0.027), even after adjustment for sex, presence/absence of anti‐AchR antibodies and presence/absence of anti‐Titin antibodies. Out of 39 patients with EOMG, who underwent thymectomy, 18 patients (46%) had thymoma, 6 had thymic hyperplasia (15%), and 15 patients had thymic atrophy (39%); there was no difference comparing EBNA‐1 antibody titers in the sera. As no correlation was found between the titers of anti‐AchR, anti‐Titin, and EBNA‐1 antibodies, a dysregulated heterogeneous B‐cell response was unlikely to be responsible for the elevated levels of EBV‐associated antibody in patients. Conclusions: In summary, our data suggest that high levels of EBNA‐1 antibodies are more common in MG compared to healthy controls and are especially associated with EOMG.     

A tri-modal distribution of age-of-onset in female patients with myasthenia gravis is associated with the gender-related clinical differences

Background: A tri-modal distribution of age-at-onset emerged among females patients with myasthenia gravis (MG) in our database. This finding may be indicative of different gender-based disease mechanisms.

Methods: We retrospectively reviewed the files of 127?MG patients for the clinical, serology and thymus pathology according to their age at disease onset: ≤40 years (early-onset, EOMG), 40–70 years (intermediate-onset, IOMG) and >70 years (late-onset, LOMG).

Results: EOMG was more common among females, and IOMG was more common among males. Ocular MG was more common among the male MG patients with an IOMG. Patients with EOMG had lower rates of positive anti-acetylcholine receptor (anti-AChR). IOMG females, but not IOMG males, had lower rates of positive anti-AChR. IOMG and EOMG females had high rates of thymic hyperplasia, while EOMG males had high rates of thymoma. Comorbidity with autoimmune diseases was common among females with IOMG and LOMG.

Conclusions: The prevalence of IOMG was the reason for the trend reversal of MG prevalence between genders. The clinical features of patients with IOMG differed between genders in the rates of positive anti-AChR, follicular hyperplasia of the thymus and comorbidity with autoimmune diseases. This may suggest a different gender-based mechanism of immune intolerance towards AChR and other antigens.     

Clinical and CN-SFEMG evaluation of neostigmine test in myasthenia gravis

Neostigmine test (NT) is a pharmacological test, demonstrating a clinical improvement in patients affected by myasthenia gravis (MG). We aim to compare clinical evaluation and neurophysiological recordings by concentric-needle single-fiber electromyography (CN-SFEMG) in response to acute administration of neostigmine in ocular and generalized MG patients. Twenty-three MG patients (10 with ocular MG and 13 with generalized MG) were evaluated before and after 90 min neostigmine 0.5-mg administration. Clinical responsiveness was assessed by MG composite (MGC) scale. Neurophysiological evaluation by CN-SFEMG considered analysis of mean value of consecutive differences (MCD), single-pair jitter, and blocks. MGC scores significantly improved after NT in generalized MG patients (MGC 11.1?±?7.6 vs 9.1?±?6.7, p?=?0.02), whereas the improvement was not significant in the ocular group. CN-SFEMG recordings significantly improved after NT in generalized MG patients (MCD 58.9?±?18.8 vs 45.9?±?23.2 μs, p?=?0.003; single-pair jitter 49.8?±?26.9 vs 24.1?±?26.7%, p?=?0.0001; blocks 6.2?±?9.5 vs 2.6?±?7.4%, p?=?0.03) as well as in ocular MG patients (MCD 50.8?±?22.7 vs 40.1?±?22.9 μs, p?=?0.01; single-pair jitter 35.9?±?23.7 vs 20.0?±?25.1%, p?=?0.001). CN-SFEMG is a reliable tool to evaluate responsiveness to acute administration of neostigmine in MG. Moreover, neurophysiological modifications to NT could show subclinical improvement in ocular MG better than that of the clinical scale.     

家族性重症肌无力临床特点及其与人类白细胞抗原DQA1基因多态性的相关性研究

目的探讨家族性重症肌无力(MG)的临床特点及其与人类白细胞抗原(HLA)DQA1基因多态性的相关性。方法对15例家族性、36例散发性MG患者的临床特点进行研究,并运用聚合酶链反应序列特异性引物(PCR SSP)对HLA DQA1基因多态性进行分型。结果与散发性MG相比,家族性MG患者发病年龄较早(两者分别为18 7、34 4岁,P=0 006),病情较轻,预后较好;与散发MG组及健康对照组比较,家族性MG患者的DQA1 0301基因频率增高(三者分别为40 0%、19 4%和20 2% ),差异有统计学意义(P<0 05),这种差异在眼肌型的患者中同样存在,但未发现患者性别与DQA1相关。结论家族性MG有其独特的临床特点,DQA1 0301是家族性尤其是眼肌型MG的易患基因,提示家族性MG与散发MG可能有着不同的免疫遗传机制。     

Myasthenia gravis appearing after thymectomy

We aimed to evaluate the clinical characteristics of patients with postoperative myasthenia gravis (MG). We retrospectively studied the data of 174 thymoma patients treated between 1990 and 2008 in Xiangya Hospital. Six of 125 patients without preoperative MG (4.8%) developed postoperative MG. The anti-acetylcholine-receptor binding antibody (ARAb) titers were elevated preoperatively in 22 of the 125 patients (17.6%) who did not have preoperative MG (range, 0.5-67.6 nmol/L). Four of six patients with postoperative MG had positive ARAb levels preoperatively. Serum titers were exacerbated in all six patients at the onset of postoperative MG. Postoperative MG was responsive to anti-cholinesterase compounds and/or steroids. We concluded that a thymectomy did not prevent postoperative MG. Exacerbated ARAb levels after thymectomy suggested an extrathymic production of ARAb. We suggest that a rise in the ARAb titer might be a risk indictor for post-thymectomy MG.     

High frequency of allergic conjunctivitis in myasthenia gravis without thymoma

OBJECTIVES: To investigate the frequency of allergic disorders in myasthenia gravis (MG) patients and characterize the features of MG associated with allergic disorders. METHODS: Frequencies of past and present common allergic disorders in 160 MG patients who visited the Department of Neurology, Kyushu University Hospital from April 2000 to July 2003 and in 81 neurological normal controls were studied. RESULTS: Among various allergic disorders, the frequency of allergic conjunctivitis (AC) was significantly higher in MG patients (39/160, 24.4%, p(corr)=0.0112), especially with MG without thymoma (36/123, 29.3%, p(corr)=0.0016), in comparison to the controls (6/81, 7.4%). MG patients with AC showed a significantly higher rate of seronegative MG (43.6% vs. 17.4%, p=0.008) and a higher tendency of ocular MG (43.6% vs. 28.1%, p=0.071). Moreover, MG with AC had significantly lower anti-acetylcholine receptor antibody titers (median 6.8 nmol/l vs. median 23.6 nmol/l, p=0.0359) as well as a lower rate of coexisting thymoma (7.7% vs. 17.4%, p=0.016). The incidence of myasthenic crisis was also lower in MG with AC than without AC, yet the difference was not significant (7.7% vs. 15.7%). CONCLUSION: There was a significant association of AC with MG especially for ocular or seronegative MG in cases without thymoma.     

Myasthenia gravis in children: a longitudinal study

BACKGROUND: Juvenile myasthenia gravis (JMG) is an uncommon disease. Unlike adults, clinical characteristics and outcomes of myasthenia gravis (MG) are not well studied in children. PATIENTS AND METHODS: Case records of 77 patients with MG who were 15 years of age or less at disease onset, evaluated over a period of 34 years at the National Institute of Mental Health and Neurosciences, Bangalore, India, were reviewed. Their clinical characteristics and response to therapy was compared with 290 patients with MG onset after 15 years of age. RESULTS: Median age at onset was 8 years and mean period of follow-up was 6.2 years (range 6 months to 25 years). At presentation, 30% of patients had ocular myasthenia and the rest had generalized disease. Twenty-one patients (27%) had disease confined to ocular muscles throughout the course and three had limb girdle myasthenia. Familial myasthenia was more common than adult onset disease, 10 patients had positive family history. Unlike adults, none of the patients had associated autoimmune disease. Fifty-two patients (67%) received corticosteroids, and azathioprine was added in five patients. Thymectomy was performed in 11 patients, six below the age of 15 years. Thymic histology was normal in one and showed hyperplasia in eight and thymoma in one. Four patients had crisis. At the end of follow-up, 25 patients were asymptomatic, 28 had partial improvement, and nine remained unchanged or worsened and two died. Ten patients achieved complete stable remission. CONCLUSIONS: This study shows some distinctive characteristics of JMG, such as higher frequency of ocular myasthenia, benign course, better long-term outcome and lack of association of thymoma and other autoimmune disorders.     

Clinical delineation of myasthenia gravis in the Kingdom of Bahrain

Objectives:To report demographic and clinical data on 98 myasthenia gravis (MG) patients, seen over 5 years (January 2014-December 2018).Methods:This was a retrospective, observational cohort study carried out at 3 hospitals in Bahrain. MG was classified into ocular or generalized types. We subdivided MG into early-onset (EOMG, ≤ 49 years) or late-onset (LOMG, > 49 years). Demographic and clinical data were recorded. The data was entered and analyzed using SPSS version 26.0.Results:61.2% were females. The mean age at onset was 43.8±17.7 years in males and 43.1±15.7 years in females. 72.4% had EOMG. A pure ocular presentation was most common (51%). Limb weakness was more prevalent in AChR-positive patients. The MuSK group had more severe presentation. 57.1% of patients were AChR-positive, 3.1% MuSK-positive, and 39.8% double-seronegative. Generalized disease onset was more likely with AChR. Abnormal CT chest was seen in 24/69 (35%) including thymic hyperplasia, thymoma, and thymic atrophy. Pathology findings were thymic hyperplasia (55.0%), thymoma (30%), thymolipoma (10%), and normal thymus (5%). Treatment outcomes were favorable.Conclusion:The present study revealed that MG was more common in females, with similar age at onset between males and females. The majority of patients had EOMG with ocular disease and AChR positivity. The clinical outcomes were favorable. Following a standardized protocol for MG diagnosis and workup is recommended.

Myasthenia gravis (MG) is an autoimmune disease of neuromuscular transmission, characterized by fatigable muscle weakness,¹ mediated by an antibody attack on components of the postsynaptic membrane of the neuromuscular junction, such as the acetylcholine receptor (AChR), muscle-specific tyrosine kinase (MuSK) and lipoprotein receptor-related protein 4 (LRP4).^2,3 This may result in various distribution of muscle weakness among different patients, including ocular and limb weakness, bulbar involvement, and sometimes respiratory failure, as well as various degrees of severity.^2,4,5 The MG is the major disorder that affects the neuromuscular junction, while other rarer syndromes include the Lambert-Eaton myasthenic syndrome and botulism, both affecting the presynaptic neuromuscular junction.⁴ The Myasthenia Gravis Foundation of America (MGFA) clinical classification (class I ocular, class II mild generalized weakness, class III moderate generalized weakness, class IV severe weakness, and class V needing intubation) is used to identify subgroups of MG patients sharing certain clinical features or disease severity, which may help predict disease prognosis and treatment outcome.⁶Based on serum antibody profile and clinical phenotypes, MG can be classified into seven subgroups: early-onset MG (EOMG), late-onset MG (LOMG), thymoma-associated MG, MuSK MG, LRP4 MG, ocular MG, and seronegative (SN) generalized MG.^4,5,7 This classification is clinically useful, as there are important differences in terms of clinical features, thymus abnormalities, treatment outcome, and drug adverse events among different phenotypes.^2,5 For example, Deymeer et al⁵ compared the clinical characteristics of 32 anti-MuSK MG, 161 anti-AChR MG and 33 SN MG patients. The MuSK MG group had more bulbar involvement and more severe disease with crises, while the SN group had a milder disease with a good outcome and lower percentage of steroid maintenance doses and use of other immunosuppressants such as azathioprine. Females predominated in all 3 groups.In general, the prognosis of MG is good, due to early diagnosis and availability of symptomatic treatment, and the use of effective immunosuppressants and other supportive measures.⁴ The aim of our study was to retrospectively gather data on the clinical characteristics of MG patients in the Kingdom of Bahrain, and compare it with regional and international data.     

Prematurity and early-onset juvenile myasthenia gravis.

A child manifested ocular myasthenia gravis at age 16 months which progressed to bulbar and mild systemic weakness over a 3-year period. The medical history was significant for premature birth at 32 weeks gestation and birth weight 940 gm. A review of reported patients with juvenile myasthenia gravis with adequate documentation of the birth history, noncongenital onset, typical clinical course and diagnostic findings, and elevated titers of antiacetylcholine receptor antibodies revealed that 55% with onset before age 3 years had a history of prematurity. This association of myasthenia gravis and prematurity may provide insights to the pathogenesis of the disease.     

Clinical and experimental features of MuSK antibody positive MG in Japan

We investigated the presence of antibodies (Abs) against muscle-specific tyrosine kinase (MuSK) in Japanese myasthenia gravis (MG) patients. MuSK Abs were found in 23 (27%) of 85 generalized seronegative MG (SNMG) patients but not in any of the ocular MG patients. MuSK Ab-positive patients were characterized as having female dominance (M:F, 5:18), age range at onset 18 to 72 (median 45) years old, and prominent oculobulbar symptoms (100%) with neck (57%) or respiratory (35%) muscle weakness. Limb muscle weakness was comparatively less severe (52%), thymoma absent. Most patients had good responses to simple plasma exchange and steroid therapy. MuSK IgG from all 18 patients was exclusively the IgG 4 subclass and bound mainly with the MuSK Ig 1–2 domain. Serial studies of 12 individuals showed a close correlation between the variation in MuSK Ab titers and MG clinical severity ( P  = 0.01 by Kruskal–Wallis). MuSK Ab titers were sharply decreased in patients who had a good response to early steroid therapy or simple plasma exchange, but there was no change, or a rapid increase on exacerbation after thymectomy. Measurement of MuSK Ab titers aids in the diagnosis of MG and the monitoring of clinical courses after treatment.     

Increased binding of anti-acetylcholine receptor antibodies to thymic antigen in patients with myasthenia gravis and other autoimmune diseases, as compared to those with myasthenia gravis alone

We compared the binding activity against acetylcholine receptors solubilized from human muscle (AChRM) and human thymus (AChRT), of sera from patients with myasthenia gravis (MG) alone, to those of sera from patients with myasthenia gravis and associated autoimmune diseases (MG AD). The sera of the MG AD group bound relatively better to thymic antigen (86% vs. 62%). This group was found to contain a higher proportion of women over 40 years of age (more than 50% of the group). The expression of a particular AChR antigen in normal human thymus may be one of the factors involved in the pathogenesis of MG, especially when this disease is associated with other autoimmune disorders.     

Anti-titin antibodies in myasthenia gravis: tight association with thymoma and heterogeneity of nonthymoma patients

BACKGROUND: Titin is the major autoantigen recognized by anti-striated muscle antibodies, which are characteristic of generalized myasthenia gravis (MG). OBJECTIVE: To seek a correlation between anti-titin antibodies and other features of MG patients, including histopathology, age at diagnosis, anti-acetylcholine receptor (anti-AChR), autoantibody titers, and clinical severity. METHODS: A novel, highly specific radioligand assay was performed on a large group of 398 patients with generalized MG. RESULTS: Among thymectomized patients, anti-titin antibodies were present in most patients with thymoma (56/70 [80%]), contrasting with only a minority of patients with thymus atrophy or hyperplasia (17/165 [10%]). They were also present in 64 (41%) of 155 nonthymectomized patients who had a radiologically normal thymus. In these patients and in those who had a histologically normal thymus, anti-titin antibodies were associated with a later age at onset of disease and with intermediate titers of anti-AChR antibodies. After controlling for these 2 variables, disease severity was not significantly influenced by anti-titin antibodies. CONCLUSIONS: Anti-titin antibodies are a sensitive marker of thymoma associated with MG in patients 60 years and younger, justifying the insistent search for a thymoma in MG patients of this age group who have these antibodies. In nonthymoma patients, anti-titin antibodies represent an interesting marker complementary to the anti-AChR antibody titer, identifying a restricted subset of patients. These clinical correlations should prompt further studies to examine the mechanisms leading to the production of anti-titin antibodies.     

Antigen-specific T-cell activation in hyperplastic thymus in myasthenia gravis

In order to determine whether antigen-specific T-cell activation by dendritic cells (DCs) is accelerated in thymuses exhibiting lymphofollicular hyperplasia (TLFH) among patients with early-onset myasthenia gravis (EOMG), we investigated the expression levels of phosphorylated protein kinase C (PKC)theta and the local relationship between the presence of phosphorylated PKCtheta and the homing receptor CD44 or CD83, a marker for mature DCs, in samples taken from EOMG patients with early improvement following thymectomy, in remnant thymuses from late-onset MG patients, and in non-MG control thymuses. Antigen-specific T-cell activation was markedly accelerated in TLFH from EOMG patients. Activated T cells and adjacent DCs appeared to be components of a CD44(high) cell population circulating from the blood to the thymus. Although there is no convincing evidence that thymectomy is of benefit in MG, in some EOMG patients with early improvement following thymectomy, blockade of CD44-associated circulation mechanisms is probably the cause for the early benefits of thymectomy and is a potential alternative to thymectomy.     

Nonthymoma early-onset- and late-onset-generalized myasthenia gravis--a retrospective hospital-based study

OBJECTIVE: Acquired myasthenia gravis (MG) is predominantly due to nicotinic acetylcholine receptor (AChR) autoantibodies (Ab). Differences between nonthymoma early-onset and late-onset MG were reported. We studied the clinical and serological characteristics of nonthymoma AChR Ab-positive-generalized MG patients. PATIENTS AND METHODS: Chinese AChR Ab-positive-generalized MG patients who had generalized disease for 3 years or longer were studied. RESULTS: Among 41 such patients, 25 (61%) were female. The mean onset age was 43.5 years (range 9-78 years) and the mean follow-up duration was 7.8 years (range 3-20 years). Sixteen (39%) patients had late-onset disease (onset age >or=50 years). Compared to early-onset patients (onset age <50 years), late-onset patients were characterized by male predominance (p=0.002), absence of thymic lymphofollicular hyperplasia (p=0.036), and a higher striated muscle Ab seropositivity rate (94% versus 4%, p<0.001). Although there was no statistically significant difference in clinical severity and outcome or response to treatment between late-onset and early-onset patients, 50% and 75% of late-onset patients had moderate or severe disease at onset and worst status, respectively, compared to 28% and 52% for early-onset patients at onset and worst status, respectively. Also 63% of late-onset patients had disease progressed within first 3 years compared to only 40% of early-onset patients did. CONCLUSION: Nonthymoma late-onset-generalized MG patients were common among Hong Kong Chinese, with a statistically non-significant trend that it was clinically more severe than early-onset MG but with similar clinical outcome or response to treatment; >90% of these patients were seropositive for striated muscle Ab.     

A retrospective review of 15 patients with familial myasthenia gravis over a period of 25?years

We observed, during a 25-year period, 15 patients from 6 families with autoimmune myasthenia gravis (all Chinese Han from Guangdong Province) referred to our department. Their mean onset age was 13.4 years (range 2-25 years) with 10 patients with juvenile onset. The female:male ratio was 3:2. Acetylcholine receptors antibody titers were increased in 11 patients (range 1.62-19.8 nmol/L). Thymectomy was performed in six patients, who received corticosteroids /immune inhibitor plus pyridostigmine treatments after surgery. The other patients were placed on therapy with azathioprine, cyclophosphamide, corticosteroids and acetylcholinesterase inhibitors. All patients responded well to immunosuppressants, and psychiatric symptoms were observed only in one patient who received a high dose of corticosteroids. Patients with generalized type in the same family had different presentations with variable prognosis. HLA-A 0207 was found in 9 patients (9/15), HLA-B 4601 in 11 patients (11/15), and HLA-DRB1 0901 in 12 patients (12/15). When compared to familial autoimmune myasthenia gravis in other countries, we observed peculiar characteristics of Chinese populations, such as the within-family consistency was only found in families with ocular MG type (50% of all MG families), while the pathogenetic conditions and the prognoses of the generalized MG patients may differ greatly within the same family. These findings may shed new light on the genetic predisposition and the origin of immune abnormalities of MG patients.     

Prognosis of thymectomy in myasthenia gravis patients with thymus hyperplasia

Purpose: To compare the post-thymectomy prognosis in different conditions of myasthenia gravis (MG) patients with thymus hyperplasia. Materials and methods: Collecting medical record and carrying out the follow-up study of 123 myasthenia gravis patients with thymus hyperplasia who have underwent thymectomy during the period between 2003 and 2013. Dividing into different groups based on gender, age of onset, duration of disease and Myasthenia Gravis Association of America (MGFA) clinical classification to analyze different prognosis in different groups. Results: Complete stable remission (CSR) was achieved in 71 of 123 patients (59.5%). There is no gender-related difference in achieving CSR. Patients with early onset of MG (≤40 years old) or disease duration less than 12 months had significantly higher CSR rates than those with late onset of MG (>40 years old) or disease duration more than 12 months respectively, while no difference was found in remission rate between MGFA clinical classification I and MGFA II. Conclusion: Myasthenia gravis patients with thymus hyperplasia who had thymectomy are proved to possess greater chance of achieving CSR. The onset age of disease and duration are the prognostic factors.     

Myasthenia gravis and pregnancy: clinical course and management of delivery and the postpartum phase

OBJECTIVES: To study influences of pregnancy on the time-course of myasthenia gravis (MG) and of MG on pregnancy, delivery, postpartum and newborn. METHODS: We retrospectively collected data from 100 women affected with MG, hospitalized between 1994 and 2003 in departments of Neurology of Lille University Hospital. RESULTS: Eighteen patients had a total of 36 pregnancies, occurring 7.2 years on average after MG onset. MG exacerbation occurred in 7 patients (26 percent) during pregnancy and in 4 (14.8 percent) during postpartum. One patient died of acute respiratory failure during postpartum. Delay between the onset of MG and pregnancy was the only variable significantly associated with MG exacerbation: 5.8 years when exacerbation and 9.5 years when no exacerbation (p=0.03). Seven miscarriages, two therapeutic abortions and no death at birth were reported. Levels of anti-acetylcholine receptor antibodies were abnormal in 3 of 27 newborns (11 percent), but only one (3.7 percent) developed seronegative transient neonatal myasthenia gravis. DISCUSSION: During pregnancy, the clinical course of MG is variable but exacerbations were associated with a shorter delay between MG diagnosis and pregnancy. The risk of transient neonatal myasthenia gravis is relatively small but exists even when the parturient has stable MG without elevated levels of anti-acetylcholine receptor antibodies. CONCLUSION: Our study confirms pregnancy is more difficult to manage at the beginning of MG. Given the unpredictable course of MG during pregnancy, we recommend women affected with MG to begin a pregnancy when the disease is stable.     

晚发型重症肌无力临床研究

目的探讨晚发型重症肌无力(Myasthenia gravis,MG)患者的临床特点。方法回顾性研究40例晚发型MG的临床特点并与早发型MG比较。结果晚发型MG患者男/女比例高于早发型MG,为1.22:1。晚发型MG的症状由眼肌受累演变至全身症状(占67.5%)显著高于早发型MG(占38.7%)。晚发型MG的肌无力程度较早发型MG肌无力程度严重,而且血清乙酰胆碱受体(acetylcholine receptor,AchR)抗体阳性率及抗体水平均显著低于早发型MG低,但Titin抗体阳性率及抗体水平却显著高于早发型MG。胆碱酯酶抑制剂对晚发型MG的疗效不如早发型MG。结论晚发型MG是一个免疫异质性的MG亚群,它的临床表现以及血清免疫学特点不同于早发型MG。     

重症肌无力患者汉密尔顿抑郁量表评分分析

目的探讨重症肌无力(myasthenia gravis,MG)患者汉密尔顿抑郁量表(Hamilton depression rating scale,HDRS)评分情况及其影响因素分析。方法横断面研究2013-07—2015-03作者医院就诊的188例MG患者的临床资料和HDRS评分情况,并根据HDRS评分将其分为抑郁组和非抑郁组,分析两组MG患者的临床特点及其与HDRS评分间的关系。结果所纳入MG患者男女比例为1.02∶1,眼肌型重症肌无力(ocular myasthenia gravis,OMG)和全身型重症肌无力(generalized myasthenia gravis,GMG)的比例为1.2∶1,以OMG起病和以GMG起病患者的比例为6.2∶1,病程中位数为2年,四分位数间距为1.8年,平均量化重症肌无力评分(quantitative myasthenia gravis,QMG)为(6.7±2.3)分,平均HDRS评分为(8.7±3.4)分,并发抑郁者65例,未并发抑郁者123例。影响HDRS评分和抑郁发生的相关因素包括性别(P0.01)、MG类型(P0.01)、QMG得分(P0.01)和美国重症肌无力协会(myasthenia gravis foundation of America,MGFA)分型(P0.01)、有无甲状腺功能亢进(P0.05)。结论影响MG患者HDRS评分和抑郁发生的相关因素包括性别、MG类型、QMG评分和MGFA分型、有无甲状腺功能亢进,充分认识其抑郁发生情况有利于更好地治疗MG。